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111.
Erhan Özcan Ali Riza Çetin İsmail Davut Çapar Ali Riza Tunçdemir Hale Ari Aydinbelge 《Odontology / the Society of the Nippon Dental University》2013,101(2):204-209
This study evaluated the influence of eugenol on the push-out bond strengths of fiber posts cemented with different types of resin luting agents. Seventy-two extracted maxillary single-rooted canine teeth were randomly divided into two groups of 36 teeth. Group 1, the control group, was filled with gutta-percha only (i.e., did not receive eugenol), whereas group 2 was filled with a eugenol-containing sealer. All root canals were filled and each group was divided into three subgroups. The posts in each subgroup were cemented with the following materials: subgroup 1 with a 2-step self-etching adhesive system (Clearfil Liner Bond 2V + Panavia F); subgroup 2 with a 1-step self-etching adhesive (Panavia F); and subgroup 3 with a self-adhesive (Clearfil SA Cement). Dislodgement resistance was measured using a universal testing machine. All data were subjected to ANOVA using a factorial design and Tukey test (α = 0.05). The use of the eugenol-containing sealer significantly reduced the push-out bond strength of the fiber post (P < 0.05). The push-out bond strength of Panavia F was significantly higher than those of the other groups filled with the eugenol-containing sealer (P < 0.05). The Panavia F group was less susceptible to the inhibiting effect of eugenol than were the other evaluated groups when the fiber post was cemented in the canals filled with the eugenol-containing sealer. 相似文献
112.
Necati Tatarlı Davut Ceylan Hüseyin Canaz Mehmet Tokmak Hüsniye Hacıoğlu Bay Aşkın Şeker Evren Keleş Türker Kılıç Safiye Çavdar 《Acta neurochirurgica》2013,155(11):2183-2189
Background
Only limited attention has been paid to the anatomy and clinical importance of the falcine venous plexus. The aim of this study was to evaluate the falcine venous plexus anatomically using scanning electron microscopy (SEM), and to provide guidance for neurosurgical approaches.Methods
Latex or ink was injected into the superior and inferior sagittal sinus. The falcine venous plexus lying within the connective tissue of the falx cerebri was observed by dividing the falx into thirds (anterior, middle and posterior). Further, the SEM appearance of the falcine venous plexus was evaluated.Results
The anterior third of the falx cerebri consisted of small diameter falcine venous vessels. These vessels were localized close to either the superior or inferior sagittal sinus, and none extended as far as mid-falx cerebri levels in any of the 16 cases. They communicated with either superior or inferior sagittal sinuses, but not with both of these sinuses. In the middle third of the falx cerebri, the majority of the vessels of the falcine venous plexus had larger diameter compared to those of the anterior third. These vessels extended the length of the falx cerebri levels. They communicated with both superior and inferior sagittal sinuses. In the posterior third of the falx cerebri, the vessels of the falcine venous plexuses had the largest diameter and were located at the junction of the inferior sagittal sinus and the straight sinus. They were localized at the lower two-thirds of the falx cerebri. In all cases, the dense venous networks communicated with the inferior sagittal sinus but not with the superior sagittal sinus. The falcine venous plexus observed in the posterior third of the falx cerebri was denser than in the anterior and middle portions. The SEM revealed small vessels whose diameter ranged between 42 and 138 μm. The vessels of the falcine venous plexus in the anterior third had a mean diameter of 0.42?±?0.1 mm, in the middle third a mean diameter of 0.87?±?0.17 mm, and in the posterior third, 1.38?±?0.21 mm.Conclusion
The falcine venous plexus is a network of venous channels that exists within the connective tissue of the falx; the sizes and patterns of communication of these structures showed regional differences. Neurosurgeons should be aware of the regional differences when making an incision or puncturing the falx during a surgical approach. 相似文献113.
Tevfik Yavuz Erhan Dilber Haluk Baris Kara Ali Riza Tuncdemir A Nilgun Ozturk 《Lasers in medical science》2013,28(5):1233-1239
The purpose of this study was to evaluate the influence of different surface treatments (sandblasting, acid etching, and laser irradiation) on the shear bond strength of lithium disilicate-based core (IPS Empress 2) and feldspathic ceramics (VITA VM 9). One hundred ceramic discs were divided into two groups of 50 discs each for two ceramic systems: IPS Empress 2 (group I) and VITA VM 9 (group II). Each of the two groups was further divided into five surface treatment groups (ten each) as follows: group SB, sandblasting with alumina particles (50 μm); group HF, 5 % hydrofluoric acid etching; group L, Er:YAG laser irradiation (distance, 1 mm; 500 mJ; 20 Hz; 10 W; manually, noncontact R14 handpiece); group SB–L, sandblasting + Er:YAG laser; and group HF–L, 5 % hydrofluoric acid + Er:YAG laser. Luting cement (Panavia 2.0) was bonded to the ceramic specimens using Teflon tubes. After 24 h of water storage, a shear bond strength test was performed using a universal testing machine at a crosshead speed of 0.5 mm/min. The data were analyzed with a two-way analysis of variance (ANOVA) and Tukey's honestly significant difference tests (α?=?0.05). The two-way ANOVA indicated that the shear bond strength was significantly affected by the surface treatment methods (p?<?0.05), but there was no significant interaction between the ceramic systems. Group SB–L had the highest mean values for each ceramic system. Sandblasting, followed by Er:YAG laser irradiation, enhanced the bond strength, indicating its potential use as an alternative method. The atomic force microscopic evaluation revealed that group SB had the most distinct sharp peaks among the groups. 相似文献
114.
115.
Yalav O ülkü A Ak?am TA Demiryürek H Doran F 《The Turkish journal of gastroenterology》2012,23(3):272-278
Neuroendocrine tumors, also known as carcinoid tumors, behave like benign tumors; however, they show the characteristics of carcinoma. While more than 80% of the neuroendocrine tumors found in the liver are metastatic, primary hepatic neuroendocrine tumors are very rare. Five patients with hepatic mass who admitted to our clinic between August 2003 and July 2007 were treated surgically. Ultrasonography, computerized tomography and magnetic resonance imaging were performed in all patients. Endoscopy and colonoscopy were conducted to exclude malignancy of other sites. Hepatectomy was carried out in all patients. Diagnosis was confirmed with immunohistochemical examination. The five patients treated surgically were diagnosed as primary hepatic neuroendocrine tumor histopathologically. Abdominal pain was the most common complaint of all patients. Hepatectomy was conducted in all patients due to tumors originating from the liver lobes. Only one patient (Case 2) underwent transarterial chemoembolization before hepatectomy to reduce tumor bleeding. Owing to tumor recurrence on the left lobe of the liver in Case 2, transarterial chemoembolization was performed four years after hepatectomy. R0 resection was achieved in two patients (Cases 1 and 3). In conclusion, primary hepatic neuroendocrine tumors are very rare and asymptomatic tumors. Thus, high-sensitive laboratory and imaging examinations are required. At present, hepatectomy remains the main treatment for primary hepatic neuroendocrine tumor. 相似文献
116.
Fatma Çağlayan Murat Çakmak Osman Çağlayan Turgut Çavuşogˇlu 《Journal of investigative surgery》2013,26(4):233-237
We investigated the possible use of D -lactate as a predictor in the diagnosis of appendicitis. C-reactive protein level (CRP) and leukocyte counts were also evaluated. Venous blood D -lactate, CRP, and leukocyte counts were measured preoperatively in 53 patients undergoing surgery for appendicitis, as well as in 20 healthy subjects. Levels of all three parameters in the surgical patients were significantly higher than in the control group ( p < .05). Previous studies have shown that venous D -lactate is more specific to the intestine than CPR or leukocyte count. Based on our data, venous D -lactate, which had the lowest false-negative rate among these laboratory parameters, may be a useful diagnostic marker for appendicitis. None of these parameters were helpful in identifying the type of the appendicitis. 相似文献
117.
118.
Arife Uslu Gökceoğlu Sema Akman Sadi Köksoy Emel Şahin Mustafa Koyun Elif Çomak Çağla Serpil Doğan Halide Akbaş Ayhan Dinçkan 《Pediatric nephrology (Berlin, Germany)》2013,28(12):2377-2382
Background
An increase in the number of circulating endothelial cells (CEC) indicates endothelial damage and the risk of cardiovascular disease. The aim of our study was to investigate the association of CEC with various clinical parameters in pediatric renal transplant recipients.Methods
CEC, defined as CD45?CD146+, were enumerated by flow cytometry from the peripheral blood of 50 pediatric renal transplant recipients and 20 healthy controls. Clinical parameters, including renal function tests, fasting blood glucose, serum cholesterol and triglyceride, cyclosporine A (CsA) (trough and 2nd-hour) and tacrolimus (tac) trough blood levels and their association with CEC numbers were analyzed.Results
CEC numbers of patients were higher than those of controls (respectively, 128?±?89 cells/ml (42–468 cells/ml), 82?±?33 cells/ml (32–137 cells/ml), p?=?0.024). There was a statistically significant negative correlation between CEC numbers and glomerular filtration rate (GFR) (r?=??0.300, p?=?0.012). There was also a statistically positive association between CEC numbers and transplant duration as well as cyclosporine trough level (respectively, r?=?0.397, p?=?0.004, r?=?0.714, p?=?0.004). CEC numbers in patients on tac and CsA were similar (p?=?0.716).Conclusions
Our results demonstrate that renal transplant recipients with high CsA trough blood level, longer transplant duration, and lower GFR, are at greater risk of developing endothelial damage. 相似文献119.
Rahim Horuz Cemal Göktaş Cihangir A. Çetinel Oktay Akça Önder Cangüven Cahit Şahin Alper Kafkaslı Selami Albayrak 《International urology and nephrology》2013,45(1):129-133
Purpose
We aimed to propose a practical selection method predicting the easier radical perineal prostatectomy (RPP) cases before the operation.Methods
Fifty sequential RPP cases were divided into two groups according to the estimated difficulty of the operation (Group I: Easier, Group II: Difficult) which was assessed by using a RPP difficulty scale, constituted by three parameters (operation time, blood loss, and the judgment of the surgeon) each ranging between 1 and 3 points. As the localization parameters, skin-to-prostatic apex (SPAD) and skin-to-prostatic base (SPBD) distances and distance between bilateral ischial tuberosities (ITD) were measured. During suprapubic ultrasonography, a probe-divergence angle (PDA) and prostate volumes (PV) were recorded. These parameters were compared between the groups.Results
In Group I (n = 29) and Group II (n = 21), the difficulty scores were 4.37 (3–5) and 6.80 (6–9), respectively. Data of age, clinical stages, and findings of digital rectal examination were not different between groups. While SPBD, SPAD, and ITD values were found similar (p > 0.05), PDA and PV were significantly different. PDA was > 45 degree in 21 cases in Group I (72.4 %) and in 7 cases in Group II (33.3 %) (p = 0.011). The mean of PV was 37.4 (20–60) cc and 49.9 (30–75) cc in Group I and Group II, respectively (p = 0.001).Conclusions
While planning RPP operations, by selecting the prostate cancer cases with a prostate of low volume and localized deeper in the pelvis during suprapubic ultrasonography, urologists may have a chance to perform this technique more easily during the learning period. 相似文献120.
T. Oksay M. Nazıroğlu O. Ergün S. Doğan O. Özatik A. Armağan A. Özorak Ö. Çelik 《Andrologia》2013,45(3):171-177
The aim of this study was to investigate the gonadotoxic effects of diazinon and its mechanism of action with special reference to its possible reactive oxygen species generating potential in rat testis and the protective effect of N‐Acetyl Cysteine (NAC) on the exposure of diazinon. The vehicle was given orally to the control group and NAC, diazinon, combination of NAC and diazinon were given to three treatment groups for 4 weeks. Testis lipid peroxidation levels were higher in diazinon group than in control although lipid peroxidation levels were lower in diazinon + NAC group than in diazinon group. The reduced glutathione (GSH) levels were lower in diazinon group than in control and NAC group although its levels were higher in diazinon + NAC group than in diazinon group. Vitamin C, Vitamin E and β‐carotene concentrations were also lower in diazinon group than in control and NAC groups. Vitamin E and β‐carotene concentrations were higher in diazinon + NAC group than diazinon group. Glutathione peroxidase activity and vitamin A concentrations in the testis did not show any difference between the four groups. In conclusion, we observed that NAC treatment modulated diazinon‐induced oxidative injury in the rat testis. These findings suggest that NAC supplementation can be useful in testis oxidative injury caused by the organophosphate insecticides. 相似文献